The present disclosure relates generally to turbine components having coatings applied thereon and, more specifically, systems and methods of automated removal of coatings from turbine components.
Modern gas turbine engines operate in high temperature environments. Components in a gas turbine engine (e.g., turbine buckets, nozzles, airfoils, and shrouds) often include thermal barrier coating (TBC) systems that protect the component, and that enables the engine to operate more efficiently at higher temperatures. Known TBC systems must have a low thermal conductivity, must strongly adhere to the component, and must remain adherent throughout many heating and cooling cycles. As such, TBC systems generally include a metallic bond coating that facilitates adhering a thermally-insulating ceramic coating to the component. Thermally-insulating ceramic coatings are generally formed from metal oxides such as zirconia (ZrO2) partially or fully stabilized by yttria (Y2O3), magnesia (MgO) or other oxides, and metallic bond coatings are generally formed from oxidation-resistant diffusion coatings such as a diffusion aluminide or platinum aluminide, or an oxidation-resistant alloy such as MCrAlY (where M is iron, cobalt and/or nickel).
At least some known gas turbine engine components have a predetermined service life. However, the components may be refurbished by removing a remaining TBC system therefrom, and by reapplying a new TBC system to the components. Several known processes are generally used for removing remaining TBC systems from turbine components. Exemplary processes include, but are not limited to, mechanical grinding, acid stripping, and water jet blasting. However, without knowing the precise thickness of the remaining TBC system, it may be difficult to determine a duration in which to apply the removal process while also reducing substrate material removal. Moreover, such known processes generally must be monitored and the components manually inspected to determine whether the removal process should continue.